In
the
Swim
of
Things
From being the preserve of the rich and the famous to an amenity used by the
middle class, swimming pools have come a long way in India. From hotels, they’ve
now come home. Most residential schemes these days boast of an in-house gym
and pool – criteria seen as essential for the good life.
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Pools are more than just a hole in the ground and plenty of water. Over the years,
construction technology has changed rapidly, and today pool design may involve
knowledge of art, landscape, engineering and technology.
16
It’s clear that things are going swimmingly for pools. Ar. Roopa Sabnis Pinge
takes an in-depth look at the evolution of swimming pools, their growing popularity
in architectural projects and modern pool construction technology.
swimming pools
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Lanka, in 4th century BC. These
were decorated with flights of
steps, punkalas, or pots of
abundance, and scroll design.
There is a mention of a swimming pool
even in the Ramayana! Ayodhya,
Kiskindha and Lanka, the three cities
related to this period, were centres
of many games and sports. Swimming
was popular and it is learnt that
Ravana had a beautiful swimming pool
in Asoka Vatika. In the Mahabharata
too, people have been shown
enjoying water sports. Bhima and
Duryodhana were great swimmers. All
the Pandava and Kaurava princes, on
the invitation of Duryodhana, are also
known to have gone to the Ganges
for water games.
Swimming pools became popular in
Britain in the mid-19th century. By
1837, six indoor pools with diving
boards were built in London. The
oldest surviving swimming club in the
world is believed to be the Arlington
Baths Club in Glasgow, Scotland. The
Arlington was founded in 1870 and is
still an active club operating out of
its original Victorian building with a
21m pool.
The popularity of swimming pools
began to spread after the
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The Great Bath at the site
of Mohenjo-Daro was most likely dug
during 3rd millennium BC. This pool
is 12 by 7 metres, is lined with bricks
and covered with a tar-based sealant.
Ancient Greeks and Romans built
artificial pools for athletic training,
for nautical games and for military
exercises. Roman emperors had
private swimming pools in which fish
were also kept (hence one of the
Latin words for a pool, piscina). Gaius
Maecenas (one of the first known
patrons of arts) of Rome built the
first heated swimming pool in first
century BC. Ancient Sinhalese built
pairs of pools called Kuttam Pokuna
in the kingdom of Anuradhapura, Sri
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modern Olympic Games began in 1896
and included swimming races. In 1839,
Oxford had its first major public
indoor pool at Temple Cowley, and
swimming began to take off. Today,
swimming is a highly popular sport and
hobby the world over. The inclusion
of swimming pools in housing schemes
is probably one of the most
significant factors in the history of
residential architecture in India. It
reflected a change in lifestyle, and
in turn, ushered in more change!
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Ar. Rachana Amin, a very senior
associate at the studio of Hafeez
Contractor, believes that swimming
pools have today become a necessity,
rather than a luxury. Any scheme sells
better when better amenities are
provided by the architect — and
swimming pools top the list. Many
high-end residential schemes also use
gyms and sports facilities as the USP
of the project as the contemporary
lifestyle often does not allow enough
time to go out and exercise. So a gym,
with a swimming pool, in the
clubhouse of your own residential
society makes perfect sense!
What is a swimming pool? Simply put,
a swimming pool is a container filled
with water intended for swimming or
water-based recreation. There are
many standard sizes — the largest and
deepest is the Olympic-size swimming
pool. A pool can be built either
above or in the ground, and with
materials such as metal, plastic,
fibreglass or concrete.
Chemical
disinfectants
such
as chlorine, bromine or mineral
sanitisers, and additional filters are
often used in swimming pools to
prevent growth and spread
of bacteria, viruses, algae and insect
larvae. Alternatively, pools can be
made without chemical disinfectants
by using a bio-filter with additional
carbon filters and UV disinfection. In
both cases, pools need to have an
adequate flow rate.
Pools that may be used by many or
by the general public are
categorised as public pools; pools
used exclusively by a few people or
in a home are called private pools.
Many health clubs, fitness centres
and private clubs have public pools
used
mostly
for
exercise.
Hotels and holiday resorts have
public pools for relaxation. Hot
tubs and spas are pools with hot
water, used for relaxation or
therapy, and are common in homes,
hotels, clubs and massage parlours.
Swimming pools are also used
for diving and other water sports, as
well as for training of lifeguards and
astronauts.
Public or private, the construction
of a pool is a highly challenging job,
and requires a good knowledge of the
technicalities involved. So though an
architect may design a beautiful pool,
it is up to the swimming pool
construction specialist to execute it
well, and provide users with a
relatively maintenance-free amenity
for recreation or exercise. Oceanic
Pool Construction, in Mumbai, is one
of the well-known swimming pool
specialists who regularly work with
architects like Hafeez Contractor.
Whether it’s the pool for Seawoods,
a residential scheme in Navi Mumbai,
or for Hotel Hyatt Regency, near the
international airport in Mumbai,
About Swimming Pools
Bangalore-based Millennium Pools is also engaged in
construction of swimming pools, water bodies and spas
across India for the last 20 years. The firm takes up the
complete job - from excavation to commissioning - on
turnkey basis under the supervision of experienced
engineers. Millennium specialises in using guniting
technology for constructing pools — a technology they
have perfected along with AquaPlan, their associates in
Switzerland. The process, called M-Crete, based on the
shotcrete system (guniting or spraying concrete at high
pressure), gives a one-piece shell, with smooth, rounded
edges. This highly compacted monolithic shell is 100 per
cent waterproof, and therefore better than the poured
concrete method usually used by local contractors.
Length
Most pools in the world are measured in metres, with a
short-course pool (25m) or a long-course one (50m) being
the standard lengths. There also exist many pools 33m
long, so that 3 lengths amount to 100 m. This pool
dimension is commonly used to accommodate water polo.
The international standard is metres, and world records
are only recognised when swum in 50m pools (or 25m for
short course). In general, the shorter the pool, the faster
the time for the same distance, since the swimmer gains
speed from pushing off the wall after each turn at the
end of the pool.
Width
Most pools are between 10m and 50m wide.
Depth
The depth of a swimming pool depends on the purpose
of the pool, and whether it is open to the public or
strictly for private use. If it is a private casual, relaxing
pool, it may go from 1 to 2 m (3.3 to 6.6 ft) deep. If it is
a public pool designed for diving, it may slope from 3.0
to 5.5m (9.8 to 18 ft) at the deep end. A children’s play
pool may be from 0.3 to 1.2m (1.0 to 4 ft) deep. Most
public pools have differing depths to accommodate
different swimmer requirements. In many jurisdictions,
From
Exclusivity
to
Necessity
There was a time when people would animatedly
talk about a certain building and the residents would
boast of their address – because of a swimming
pool in the premises. Similarly two decades ago,
people chose to stay in a five-star hotel since one
of its attributes was a swimming pool.
Today every r esidential project, small or large, is
planned with one, or more, s wimming pools. With
space being a constraint in smaller buildings, pools
are located on the terrace. In their brief to architects,
developers include the provision of one, and in
case of larger residential projects, even up to three
pools! Similarly, it is no longer only five-star hotels
that are designed with swimming pools. Almost
every hotel from two-star level upwards boasts of
a pool. In fact, swimming pools have now become
an essential part of every development residential, hospitality, and even office or
institutional.
Swimming pool designs have also evolved. From
the simple rectangle, shallow on one side and
deeper on the other, swimming pools are now seen
in all shapes and sizes, made conventionally in RCC
with tiling, or in membranes, or in fibreglass with
numerous additions to it.
There are buildings being designed where each
apartment has its own little private pool on a terrace,
and there are hotels, which may have a large
lagoon pool in addition to individual pools, attached
to the larger suites.
Infinity pools, which first originated from the idea
of an elevated pool without a visible edge seen
against the backdrop of an ocean, have now
become almost mandatory – irrespective of the
backdrop! In holiday resorts, large lagoon pools
(covering an area of 1 to 3 acres) are designed to
flow gracefully around the pr operty. These are
further elaborated by the inclusion of open-air
Jacuzzis and multi-level pool areas with slides or
waterfalls between them. Many resorts also provide
water-sports as an additional attraction in their
facilities.
Water may be becoming a scarcity, but it seems
swimming pools are here to stay!
- Ar. Sanjay Puri
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Oceanic has executed some beautiful pools for
Contractor. Ar. Rachana Amin, who was the architect in
charge of both projects, is quite satisfied with the quality
and service delivered by Oceanic.
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it is a requirement to show the water
depth with clearly marked depths
affixed to the pool walls.
Types of Pools
Private Pools: Private pools are usually
smaller than public pools, on average
12 × 24 ft (3.7 × 7.3m) to 20 × 40 ft
(6.1 × 12m), whereas public pools
usually start at 80 ft (24m). Home
pools can be permanently built-in, or
be assembled above ground and
disassembled after summer.
Public Pools: Public pools are often
found as part of a larger leisure centre
or recreational complex. These
centres often have more than one
pool, such as an indoor heated pool,
an outdoor saltwater or unheated
chlorinated pool, a shallower
children’s pool, and a paddling pool
for toddlers and infants. There may
also be a sauna and one or more hot
tubs or spa pools (Jacuzzis).
If a pool is in a separate building, the
building is called a natatorium. The
building sometimes also has facilities
for related activities, such as a diving
tank. Outdoor pools are common in
warmer climates. Larger pools
sometimes have a diving board affixed
at one edge above the water. Diving
pools should be deep enough so that
divers are not injured.
Many public swimming pools
are rectangles 25m or 50m long, but
a pool may be any size and shape
desired. There are also elaborate
pools with artificial water falls,
fountains, splash pads, wave
machines, varying depths of water,
bridges, and island bars.
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Hot Tubs and Spa Pools: Hot
tubs and spa pools are common
heated pools used for relaxation and
sometimes for therapy. Commercial
spas are common in the swimming
pool area or sauna area of a health
club or fitness centre, in clubs,
motels and
exclusive five-star
hotel suites. Commercial spas are
generally made of concrete, with
a mosaic-tiled interior.
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Whirlpool tubs first became popular
in the United States during the 1960s
and 70s. A spa is also called a Jacuzzi
there since the word became
generic after plumbing component
manufacturer Jacuzzi introduced the
Spa Whirlpool in 1968. Air bubbles may
be introduced into the nozzles via an
Ocean pools: In the early 20th century, especially
in Australia, ocean pools were built typically on headlands
by enclosing part of the rock shelf, with water circulated
through the pools by flooding from tidal tanks or by
regular flooding over the side of the pools at high tide.
This continued a pre-European tradition of bathing in
rock pools, or bogey holes, with many of the current
sites being expanded from sites used by Australian
Aborigines.
Infinity pools: An infinity edge pool (also named negative
edge or vanishing edge pool) is a swimming pool that
produces a visual effect of water extending to the horizon,
vanishing, or extending to infinity. Often, the water appears
to fall into an ocean, lake, bay, or other similar body of
water. The illusion is most effective where there is a
significant change in elevation, though having a natural
body of water on the horizon is not a limiting factor.
Zero-entry swimming pools: A zero-entry swimming pool,
also called a beach entry swimming pool, is a swimming
pool having an edge or entry that gradually slopes from
the deck into the water, becoming deeper with each
step, in the manner of a natural beach. As there are no
Evolution
of the
Pool Culture
in India
Pools have been present in ancient India. Traces
of a pool can be found in Jahaz Mahal, Mandu,
and other palaces and royal residences, but
not beyond that - not in the common man’s life.
Those pools were less likely meant for
maintaining fitness and more for leisure.
Indeed, water is a refreshing and de-stressing
element of nature and a swim certainly can be
a great stress-buster! However, this is a Wester n
thought, not applicable necessarily to the Indian
mindset. We, as Indians or as individuals from
developing or third-world nations, believe in
mimicking Western values without justifying the
purpose - just as we jumped to glass structures
and now, after burning our fingers, are still
scared to return to our roots.
Unfortunately therefore in India, a pool has
become synonymous with the elite or higher
classes as their attempt to showcase their
affluence and Western style of living. Whether
in private homes or high-end residential
complexes and gated community spaces, the
trend today is to have a swimming pool as an
amenity! But is the pool ever used? Or is it
merely a status symbol? The answers to both
these questions are obvious.
In Europe and America, pools suit the lifestyle
of the people. Weather conditions also support
them. In dusty Indian conditions, poor attitude
towards physical exercise, conservative social
structuring and cultural barriers are a few very
important issues we have to address before
blinding aping the West, or imbibing their status
symbols! To some extent, individual family
dynamics and metropolitan views will have an
impact on the way Indians can use the swimming
pool – but by and large, we, as a people, are
still not very comfortable around them.
In the hospitality sector, however, a swimming
pool is a mandatory addition to the design brief.
It can offer the guests an easy way to unwind
and relax, after a hard day’s work.
- Ar. Rahul Dalvi
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air-bleed venturi pump that combines cooler air with the
incoming heated water to cool the pool if the temperature
rises uncomfortably. Some spas have a constant stream
of bubbles fed via the seating area of the pool, or a footwell area. This is more common as a temperature control
device where the heated water comes from a natural
(uncontrolled heat) geothermal source, rather than
artificially heated. Water temperature is usually very warm
to hot — 38 to 42 °C (100 to 108 °F), so bathers usually
stay in for only 20 to 30 minutes. Bromine or mineral
sanitisers are often recommended as sanitisers for spas
because chlorine dissipates at a high temperature,
thereby heightening its strong chemical smell. Ozone is
an effective bactericide and is commonly included in
the circulation system with cartridge filtration, but not
with sand media filtration due to clogging problems with
turbid body fats.
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21
stairs or ladders to navigate, this
gradual entry assists older people,
young
children
and
people
with accessibility problems.
Types of Pool Construction
The main difference between
different types of pools is how the
basin is constructed. There are
several different pool styles, each
with its advantages and disadvantages.
Above-ground pools are the
cheapest construction option as well
as the easiest to build. Most aboveground pools are made from
prefabricated kits, which even an
amateur can put together (though
most people go with professional
installers). First, the installers level
off the ground to form a flat building
surface. Then they assemble a
perimeter track, which supports the
outer wall (made of metal, plastic or
wood). Next, they spread sand in the
pool area and lay the plumbing.
Finally, they secure the vinyl liner
over the pool walls, fill the pool with
water, smooth the liner and fasten it
into place. As soon as they hook up
the pump and filtering system, the
pool is ready to go. The main
disadvantage of this sort of pool is
that it is less durable than other
designs, and generally less attractive.
It’s also less permanent, which can
be a good thing - it’s relatively easy
to disassemble the pool and move it
to a new location.
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Fibreglass pools are made from
fibreglass-reinforced plastic, which
has been moulded into a basin shape.
To install the pool, a construction
crew digs an appropriately sized
hole, lays the necessary plumbing,
adds some sand filler, and lowers the
preformed pool structure into the
hole. Then they level the pool, hook
up all the plumbing and backfill in the
area around the pool. The pool is
usually surrounded by a concrete
deck structure.
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Vinyl-lined in-ground pools are a lot
like
above-ground
pools,
structurally, but they look more like
conventional in-ground designs. The
construction crew digs a hole and
assembles a metal, plastic or wood
frame wall around the hole’s
perimeter. As in an above-ground
pool, the crew lays sand along the
bottom of the hole and secures the
vinyl lining to the structural wall.
These pools are a lot cheaper than
other in-ground designs, but not as durable. Typically,
the liner needs to be replaced every 10 years or so.
Gunite pools are the most popular design in much of the
United States. To build one of these pools, the
construction crew digs a hole, puts the plumbing in place
and assembles a framework grid with 3/8-inch steel
reinforcing rods (rebar). The rebar rods are spaced about
10 inches apart, and secured together with wire. When
the grid is in place, the crew sprays a heavy coating of
gunite, a mixture of cement and sand, around the rebar.
The sprayer unit combines dry gunite mix with water
just before spraying — this produces the wet concrete
material. The crew trowels the gunite smooth and lets it
sit for a week or so before applying a smooth finish to
the rough surface. The most popular finish is called
plaster (actually a mixture of cement and marble sand),
but a lot of people finish their pools with special concrete
paint. Gunite pools can also have tile, exposed aggregate
or even fibreglass finishes. Gunite pools (and their
cousins, shotcrete pools) are highly durable and can be
built in any shape or size.
Poured-concrete pools are similar to gunite pools, but
they’re a lot harder to build. Instead of spraying concrete
material around a rebar framework, concrete is actually
poured into conventional wooden forms. With the rise
of gunite methods, poured-concrete construction has
become less popular. In masonry block pools, the walls
are constructed with concrete blocks.
While these pool designs are quite different, they all
rely on the same basic plumbing and filtering systems.
What is Gunite?
Gunite concrete is a new innovation that has re-defined
pool design and construction all over the world. Here’s
what makes gunite concrete a watertight concept. Gunite
concrete is a rich cement-aggregate mix, with low-water
content. The compaction strengths achieved by this
process make pool walls rock-hard and impermeable.
‘Pools
are a
Necessary Amenity
These Days’
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Swimming pools and their use has changed
considerably over the past decade or so. In
metropolises, especially, the trend to have swimming
pools in all residential developments is no longer
just for marketing the project. People have become
more health conscious, and use swimming for
exercise as well as recreation. In recent and
upcoming developments, the facility of a clubhouse
with a decent-sized pool has become common – a
necessary amenity rather than jargon.
However, we are also aware of typical Indian
mentality, and therefor e in smaller towns, and even
in certain conser vative localities in the metros,
swimming pools may not be used as much. In private
homes also, swimming pools are an upward trend.
There are also more modern innovations like having
a pool and Jacuzzi combo. About 20’ long, it seems
like a nice product! Home pools, spas and
whirlpools also offer privacy. In the hospitality
sector, swimming pools are of course well used. But
in smaller Indian hotel brands, largely, one adds a
swimming pool to the brief as it is a mandatory
element in the star -classification guidelines. So
sometimes, even a small pool is made, which
otherwise may not be sufficient for proper exercise
or recreation. And since it is indeed not even used
very much, a small pool can be justified.
In terms of technology too, there are greener, safer
options for keeping the pool clean. These options
are pr eferred over chlorination as they are supposed
to keep the water fresher for a longer time.
- Ar. Khozema Chitalwala
Once the gunite concrete sets and hardens, it provides
a perfect surface for the finishing touch — with designer
tiles that can be patterned around graphics, motifs,
personal logos and existing visual concepts.
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There is more to gunite concrete than the mix. The
process uses compressed air-driven guniting guns that
shoot the mix on to steel reinforced walls, under high
pressure. Here is where expertise becomes the key input,
to ensure a spraying technique that’s precisely regulated.
The steel-reinforced structure can be easily erected
along pool contours, which adds to the flexibility of
working with free-flowing shapes and forms. The lagoon
look is extremely popular these days.
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•
•
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•
24
•
As the name implies, shotcrete is
concrete placed by “Shooting”.
“Shooting” is done by means of a
gun, so shotcrete is also called
Gunite concrete.
shotcrete and thus made leakproof.
•
A pneumatic compressor of about
450 cfm prepares a thorough mix
of cement, aggregate and sand.
This integrated dry mix is
pneumatically conveyed through
a delivery hose to a nozzle, where
adequate water is added.
Provided the water-cement ratio
and the mix is same, the
properties of shotcrete are the
same as those of traditional
concrete
in
respect
of
compressive, tensile and shear
strengths. But there is one
notable difference. Since
concrete is placed by shooting
with a tremendous force, it is
extremely compact and thereby
impermeable to water.
In fact, many existing hydraulic
structures and under ground
cavities are sealed by the use of
•
•
Another aspect distinguishing
shotcrete from ordinary concrete
is its ability to adhere to any
surface, whatever the angle of
inclination. Since it is applied in
layers, it is well compacted
immediately on placement and
compaction and the latter stage
i.e., compaction can sometimes
be faulty subject to human and
mechanical error.
Pool shell formed by shotcrete is
monolithic in nature with no
joints; whereas in conventional
poured concrete, there are
construction joints, which are
most vulnerable to leakage over a
period of time.
To prepare good concrete
thorough mixing of cement and
aggregates is very important and
this extremely well done in
shotcrete by means of pneumatic
pressure.
•
We earlier said that the
properties of concrete and
shotcrete are same, provided
water cement ratio is same. But
about 20 per cent less water is
used in shotcrete – since
workability is not a criterion and
with a lesser water-cement ratio,
shotcrete has higher compressive
tensile and shear strengths.
•
No formwork (shuttering) is
required and this has a time/cost
saving consequence. Free-form
pools are particularly possible in
a cost effective way, because
installing formwork of a free form
pool with various curves and
slopes is tedious and expensive.
•
Shotcrete is a continuous
operation and thus the completion
of a pool is accomplished in a
shorter time vis-à-vis conventional
concrete method.
Footnote
• The technical information about GuniteShotcrete Pools has been provided by
Millennium Pools.